A senior Bank of England official has made clear that the UK should not water down international rules intended to reform the banking system.

Chief cashier Chris Salmon told an audience in London on Tuesday that while few commentators doubted the need for reform because of the scale of the banking crisis, there were some calls that these changes were "too ambitious and should be watered down".

There have been warnings, for instance, that new rules setting how much capital banks should hold – designed by the supervisors in Basel, Switzerland – and the type of capital, need to be delayed given the fragile state of the economy. But, Salmon said: "Scaling back our ambitions for the reforms, for example by blurring capital definitions as some have suggested recently, or weakening the thrust of the new liquidity requirements, would involve sacrificing long-term gains and missing the great opportunity that we have to refashion the financial system."

Even so, he conceded that there is "some basis" for the concerns about flawed implementation of reforms. He said there were a number of elements to the UK's approach. For instance, managing the cost of change by having a long transition period rather than water it down and implement the changes more quickly. He made clear the Bank will not give way on new requirements to publish liquidity ratios from next year, as set out by the Financial Policy Committee. He admitted that the regulators need to have rules that can be "amended, recalibrated or adjusted" to cope with changes. He also said that clearing houses – which guarantee trades between big financial institutions and are known as central counter parties (CCPs)– are going to be subjected to new standards. Clearing houses might "need to modify their operations" when the new rules are introduced next year.